摘要:

AbstractA novel self‐assembly technique for the growth of insoluble and intractable thin organic films is presently reported. Bifunctional 8,8′‐dihydroxy‐5,5′‐biquinoline (bisquinoline) is reactively self‐assembled with diethyl zinc to form a linear coordination polymer. FTIR, UV/VIS spectroscopy, profilometry, and photoluminescence measurements were used to characterize these new multilayer films. The growth of these films on glass substrates was monitored by increasing absorbance at 396.6 nm using UV/VIS spectroscopy and by profilometry. FTIR spectroscopy indicated that the self‐assembled films are polymeric in nature. The reduction of end‐group hydroxyls and a significant red‐shift of the photoluminescence emission spectrum with respect to zinc bisquinoline powder was attributed to an increase in

ISSN:1022-1360    

DOI:10.1002/masy.19981250112

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractVarious difluoro functionalized aromatic 1,3,5‐triazine monomers were prepared. A series of poly‐(1,3,5‐triazine‐ether)s was synthesized by polycondensation with 4,4′‐(hexafluoroisopropylidene)diphenol. The polymers have excellent thermal stability and are amorphous with glass transition temperatures in the range of 190–250°C. In order to examine the potential to apply these polymers in organic electroluminescent devices, the redox properties were studied by cyclic voltammetry. It was found that the monomers have high electron affinity and reach LUMO values in the range of −2.7 to −3.1 eV. This opens the possibility to utilize 1,3,5‐triazine containing materials as electron injecting/hole blocking layer in LEDs. First LED results are in accordance to these high

ISSN:1022-1360    

DOI:10.1002/masy.19981250113

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractWe synthesized low molecular weight triphenyldiamines (TPDs), novel 1,3,5‐tris(diarylamino)benzenes (TDABs), polymeric triphenyldiamines and insoluble triphenylamine networks based on tris(4‐ethynylphenyl)amine as hole transport materials for electroluminescent displays. The HOMO energy values as determined from cyclic voltammetry measurements for TPDs and TDABs are between −4.97 and −5.16 eV. By using a polymeric TPD as hole transport layer and tris(8‐quinolinolato) aluminium as emitter, LEDs with an onset voltage of 3V and a luminance up to 900 cd/m2were obtained under ambient c

ISSN:1022-1360    

DOI:10.1002/masy.19981250114

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractThe syntheses of partially conjugated alkoxy substituted Poly(p‐phenylenevinylene) (PPV) materials with tertiary amines and cationic species covalently bound to the polymer backbone are described. The amine/cationic species are introduced via a polymer analogous reaction of a functional alcohol and the chloro‐precursor polymer. Single layer, polymer light emitting diodes (PolyLEDs), prepared with the modified polymer materials show a strong ‘burn‐in’ effect, leading to very high electroluminescence (EL) quantum efficiencies especially with higher workfunction

ISSN:1022-1360    

DOI:10.1002/masy.19981250115

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractFor the purpose of developing an amorphous molecular material with a high glass‐transition temperature (Tg) and a low ionization potential for use as a charge‐transport layer in organic electroluminescent (EL) devices, a novel starburst molecule, 4,4′,4“‐tris[bis(4′‐tert‐butylbiphenyl‐4‐yl)amino]triphenylamine (t‐Bu‐TBATA), was designed and synthesized.t‐Bu‐TBATA was found to form readily a stable glass with a Tg of 203 °C. A multilayer EL device consisting of double hole‐transport layers oft‐Bu‐TBATA and 4,4′,4“‐tri(N‐carbazolyl)triphenylamine and an emitting layer of tris(8‐quinolinolato)aluminum was fabricated and its performances were examined. The device was found to exhibit good performances and to b

ISSN:1022-1360    

DOI:10.1002/masy.19981250116

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractNovel hole and electron transporting materials have been synthesized to improve the thermal stability of organic electroluminescent (EL) devices. Molecular structures of such hole and electron transporting materials were designed based on triphenylamine (TPA) and oxadiazole (OXD) moieties, respectively. It has been found that the resulting materials have high glass transition temperatures (Tg) over 100°C and the vacuum‐deposited thin films are significantly thermally stable. For the two‐layer EL devices using the novel hole transporting materials and the typical emitting material, tris(8‐quinolinolato) aluminum, the thermal stability has been clearly seen to depend on the Tg of the hole transporting material; excellent thermal stability was achieved. For the three‐layer EL device using the novel electron transporting material, good emission efficiency and good stability were achieved. The electron transporting materials have been also applied to the polymeric system with polyvinylcarbazol

ISSN:1022-1360    

DOI:10.1002/masy.19981250117

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractA new precursor route for poly(arylene vinylene) derivatives will be presented. In this way non‐ionic precursor polymers are obtained which show an enhanced thermal stability and are soluble in organic solvents. This enables a thorough structural characterization and the study of the mechanism. Experiments have been performed to differentiate between a radical or an ionic polymerization mechanism. Furthermore possibilities to tune solubility characteristics and to introduce defects in the polymer backbone will be discussed. Also the scope for this new route was explored. The first results indicate that the versatility exceeds that of the Wessling route, e.g. the synthesis of precursors for poly(p‐biphenylene vinylene) and poly(2,6‐naphthylene vinylene) could be accomplished in our case, whereas it failed in the case of the Wessling

ISSN:1022-1360    

DOI:10.1002/masy.19981250118

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

摘要:

AbstractThe synthesis of several highly phenylated PPV derivatives by a chlorine precursor route (CPR) was investigated in order to understand its scope. Three 1,4‐bis(chloromethyl)benzene monomers were prepared via a robust and versatile synthetic procedure involving the Diels‐Alder reaction. The monomers were then polymerized to the corresponding precursor polymers with about 1.0 equivalent of potassium t‐butoxide in THF. Only one monomer gave a soluble precursor polymer while the other two gave insoluble precursor polymers. The soluble precursor polymer was deposited as thin films and then converted to the corresponding PPV derivative, which showed green photoluminesence and electrolumine

ISSN:1022-1360    

DOI:10.1002/masy.19981250119

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY

ISSN:1022-1360    

DOI:10.1002/masy.19981250101

出版商:Hüthig&Wepf Verlag    

年代:1998

数据来源: WILEY